Plumbing of a sanitary and hygienic sink or other fixture having a drain necessitates employing a trap, to act as a vapor barrier, against noxious or even unsanitary odors, vermin, bacteria and the like passing to an open drain hole in a sink, for example, and the conduit to a sewer system or septic holding tank. Even a kitchen sink requires such a trap. Such traps are configured so as to retain a small amount of water in a U-shaped bend, this water then acts to prevent any reflux of undesirable gases, particles and pests from entering into bathroom, kitchen, laundry room or other space through an otherwise open drain. The use of such traps has been known for hundreds of years, and more recently has become a matter of code or building regulations. Without the use of such traps, the typical drain to a sewer system would become an open pathway for foul odors and disease carrying pathogens.
The U or P bend is normally disposed underneath a fixture to be drained, whether that is a floor drain, a laundry drain, or a sink. The space under an exemplary bathroom or kitchen sink is very limited, however, which means that the system of piping must not take up excessive space. On a practical basis, just getting the various types of fixture drains to run to the trap and thence to the outlet from the space is hard enough without adding large or bulky additional devices to the system. Repair of such systems is an even greater challenge: old parts must be removed within the small space, parts which have rusted together must be separated, and so on. The P-trap has the benefits of being relatively small and easy to manufacture at low cost, and it would not be desirable to attempt to use large or expensive systems in conjunction with such P-traps.
The actual U-shaped bend may be called a U-bend or U-trap, and forms one portion of the larger P-trap. For use in this application, the term P-trap will be used, but the term should be understood to apply to the U portion and other terms for or types of vapor barrier traps. More specifically, a conventional trap is typically made using the U bend to which the plumber or builder attaches, a J bend at the outlet leg of the U, thus defining a generally horizontal outlet and making the signature “P” shape from the “U” and the straight outlet. The outlet of course is then be connected to conduits connected to the sewer or septic system for the disposal of liquid wastes.
Thus a conventional P-trap is formed from generally tubular drain fittings, which may be fabricated from either metal or plastic. For plastic fitting P-traps the inlet leg of the U is frictionally coupled in physical engagement using a nut and either a rubber gasket or beveled compression washer collar fitting so as to firmly grip a vertical drain pipe which extends down from the fixture to be drained. Typically the various joints of the system (for example between the J bend and the U bend) are joints which are detachable joints held together by a threaded connector.
It is worth noting at this point that assembly of the system depends on getting lengths of the various components correct. This would be relatively easy if part sizes and lengths were standardized to meet standard drain locations, standard sink and bath sizes and so on, but in reality, the installation process is made harder because all lengths of the pipes must meet to make a complete system which does not suffer from an excessive amount of tension, torsion or other stress or strain: such forces may eventually cause leaks or damage to parts. Thus, in addition to the need to avoid large or bulky additions to the system, it is desirable to avoid adding any elements which are of substantial length.
Such a P-trap may be installed as follows. First the drain pipe from the sink and the drain conduit connecting the sink to the septic or sewer system are roughed in to an approximate location. The ends of these pipes will be generally in the same area, but not attached. Then the P-trap is installed between the free ends of the two pipes. The P-trap, comprising the J-bend and the U bend are loosely threaded together, then the threaded joint can be adjusted for further manipulation of the pipes.
Turning to consideration of drainage of such P-traps, it will be understood that the P-trap dramatically alters the fluid flow within the system of pipes beneath the fixture drain. A straight vertical pipe has certain flow characteristics (fast flow or fall of water), a steeply angled pipe slightly different ones (ability to carry a substantial amount of matter), a flat pipe may have different flow patterns (no flow unless water is flowing into it at to provide pressure to cause flow to occur), an angled bend has other characteristics (a sharp flow disruption which may cause material to settle out) and so on. The complexity of flow within a P-trap may be understood if it is considered that the typical P-trap actually has a vertical drop, a curved section at various angles, a sharp elbow and a nearly horizontal run afterwards.
The natural result is well known to all homeowners. P-traps get clogged. The typical household has at least one individual who lets their hair or whiskers go down at least one drain, greasy materials may be put down the drain (for example, from washing of greasy hands), and without thinking, individuals continuously place obviously flow impeding materials into drains: all types of dirt, greases and oils of all types and so on. Eventually the P-trap clogs, the drained fixture becomes unusable and it becomes necessary to remove it or replace it at considerable expense and trouble. It is obviously desirable to make P-traps as difficult to clog as possible.
In addition, the typical P-trap flow disruption also alters the fluid flow within the pipe. For example, laminar fluid flow (in which the water flows in generally smooth or even layered patterns straight along the pipe) may give way to turbulent fluid flow (in which the water flows in less organized ways and with a greater degree of motion in three dimensions).
It would be advantageous to provide a device which alters the fluid flow within a trap so as to increase the efficiency of flow through the trap, in terms of flow rate, reduced chance of clogging or the like.
It would be advantageous to provide a device which is short in length in terms of the system of pipes of a P-trap drain, so as to allow easy installation in diverse plumbing traps despite the space and length limitations of such systems.
It would be advantageous to provide a device which is low in cost, easy to manufacture and easy to install in a typical P-trap drain.